export const MOTION_PROVIDER_BROWSER = "browser_camera";
export const MOTION_PROVIDER_AGENT = "motion_agent";
export const DEFAULT_MOTION_PROVIDER = MOTION_PROVIDER_BROWSER;
export const MOTION_PROVIDERS = new Set([
  MOTION_PROVIDER_BROWSER,
  MOTION_PROVIDER_AGENT,
]);
export const MOTION_GESTURES = new Set([
  "rotate_left",
  "rotate_right",
  "rotate_up",
  "rotate_down",
  "zoom_in",
  "zoom_out",
  "focus_prev",
  "focus_next",
  "layer_prev",
  "layer_next",
  "confirm",
]);

export function clamp01(value, fallback = 1) {
  const number = Number(value);
  if (!Number.isFinite(number)) return fallback;
  return Math.max(0, Math.min(1, number));
}

export function normalizeMotionProvider(value, fallback = DEFAULT_MOTION_PROVIDER) {
  const normalized = String(value || "").trim();
  if (normalized === "browser") return MOTION_PROVIDER_BROWSER;
  if (normalized === "agent") return MOTION_PROVIDER_AGENT;
  return MOTION_PROVIDERS.has(normalized) ? normalized : fallback;
}

export function normalizeGestureMessage(raw, fallbackSource = "motion-provider") {
  if (!raw || typeof raw !== "object") return null;
  if (raw.type !== "gesture") return null;
  const gesture = String(raw.gesture || "").trim();
  if (!MOTION_GESTURES.has(gesture)) return null;
  return {
    type: "gesture",
    gesture,
    phase: raw.phase || "discrete",
    confidence: clamp01(raw.confidence, 0),
    intensity: clamp01(raw.intensity, 1),
    timestampMs: Number(raw.timestamp_ms || raw.timestampMs || Date.now()),
    seq: Number(raw.seq || 0),
    source: raw.source || fallbackSource,
    mode: raw.mode || "single",
    protocolVersion: raw.protocol_version || raw.protocolVersion || "motion.v1",
    cameraId: raw.camera_id || raw.cameraId || "unknown",
    inputMode: raw.input_mode || raw.inputMode || raw.mode || "single",
    fusion: raw.fusion && typeof raw.fusion === "object" ? raw.fusion : null,
    payload: raw.payload && typeof raw.payload === "object" ? raw.payload : {},
  };
}

export function normalizeSkeletonMessage(raw, fallbackSource = "motion-provider") {
  if (!raw || typeof raw !== "object" || raw.type !== "skeleton") return null;
  const joints = Array.isArray(raw.joints)
    ? raw.joints
        .map((joint) => {
          const id = String(joint?.id || "").trim();
          const x = Number(joint?.x);
          const y = Number(joint?.y);
          if (!id || !Number.isFinite(x) || !Number.isFinite(y)) return null;
          return {
            id,
            x: clamp01(x, 0),
            y: clamp01(y, 0),
            confidence: clamp01(joint?.confidence, 1),
          };
        })
        .filter(Boolean)
    : [];
  const bones = Array.isArray(raw.bones)
    ? raw.bones
        .map((bone) => {
          if (!Array.isArray(bone) || bone.length < 2) return null;
          const from = String(bone[0] || "").trim();
          const to = String(bone[1] || "").trim();
          return from && to ? [from, to] : null;
        })
        .filter(Boolean)
    : [];
  return {
    type: "skeleton",
    timestampMs: Number(raw.timestamp_ms || raw.timestampMs || Date.now()),
    source: raw.source || fallbackSource,
    mode: raw.mode || "single",
    cameraId: raw.camera_id || raw.cameraId || "unknown",
    matchedGesture: raw.matched_gesture || raw.matchedGesture || null,
    confidence: clamp01(raw.confidence, 0),
    joints,
    bones,
  };
}